Power winding of strip material



Aug. 11, 1953 ov 2,648,502

' POWER WINDING 0F STRIP MATERIAL Filed May 31, 1949 INVE NTOR. 167702917701 BY W ' HTTOEJVE) Patented Aug. 11, 1953 UNITED STATES PATENTOFFICE POWER WINDING F STRIP MATERIAL Lev A. Trofimov, Willoughby, OhioApplication May 31, 1949, Serial No. 96,372

21 Claims. 1

This invention relates to power winding of strip materials, wire, etc.onto drums, reels, or the like; and particularly to apparatus forcontrolling the rotary speed of the drum and the tension of the strip,as the diameter of the roll of material being wound on the drumincreases.

The invention is particularly applicable to the winding of materialsonto a drum rotatively driven by a motor, when the material is suppliedto the drum at a known linear speed, for example, as the material comesfrom a material producing or processing apparatus or machinery, and itis desired to control the tension of the strip.

The diameter of the accumulating roll of material being wound on a drumis, of course, small at the start of the winding operation, andincreases as the winding proceeds; and, when the material is supplied tothe drum at a known average speed or substantially constant speed,increasing tension will develop in the strip, in the absence of somemean to prevent it, and the tension may reach values damagin to thestrip, or even to the apparatus to which it is connected, and from whichit is supplied.

It is evident and known that if the tension is to be prevented fromincreasing in direct proportion to the increasing diameter of the roll,the speed of the drum must be reduced as winding goes on. But beyondthis one essential requirement, controls as thus far devised in this arthave differed as to their essential characteristics and fall into twogeneral classes, corresponding to two different concepts about winding.

In one class as the motor speed is reduced, tension in the strip ismaintained constant, the motor developing increasing torque atdecreasing speed or constant horsepower.

In the other class as the motor speed is reduced, the torque ismaintained constant, the tension in the strip decreases as winding goeson, and the motor develops a tapering or decreasing horsepower.

There are cases to which each of these classes of control is adapted;but neither of them is satisfactory for all cases because of diiferencesin the materials that may be wound.

In the first case, the constant tension control, if the strip materialis fabric or is linoleum or paper or cellophane for example, then whenthe diameter or radius of the roll increases, the tangential force on itouter convolutions may cause the inner convolutions to slip on eachother and become more tightly wound, and in some cases cause the innerconvolutions to buckle and damage them; and if the strip has a patternon it, the slipping of the inner convolutions may mutilate the pattern,and if it is a printed pattern and not entirely dry, it will be smeared.

If the constant tension is adjustably reduced to avoid this controldefect at the inner convolutions, then the outer convolutions will be soloosely wound as to untelescope when the roll is handled.

In the second case, or constant torque case, the inner convolutions aretightly wound and the outer convolution more loosely wound, and for aroll of any considerable final diameter the outer convolutions will betoo loose and Will untelescope when handled; and to prevent this theinner convolutions must be wound to excessive or even damagingtightness.

The ideal control would be one which is adapted to wind any kind ofmaterial satisfactorily and without such disadvantages as thosementioned above, by being universally adjustable, to apply motor powerto the drum at decreasing speed and at constant tension in the strip; orat changing tension, increasing or decreasing; and in the case ofchanging tension, adjustable to vary the rate of change of the tensionas the roll diameter increases to suit the requirements of theparticular installation and material.

And as a further characteristic of such ideal control, it should be onethat could be initially manufactured to embody alternatively oroptionally any of the desired characteristics of tension control, for agiven installation without having to adjust it.

It is the primary object of the present invention to provide a poweroperated winding control of this universally adjustable character; andone which, alternatively, can be constructed originally to respondwithout adjustment, to develop a predetermined tension in the stripmaterial as winding goes on.

The invention departs from prior practice in the fundamental concept ofthe control. According to the invention, the power to drive the windingdrum is supplied by a motor; any type or class of motor, and preferablyan electric motor; but the speed of the motor is not regulated orcontrolled. It runs continuously at all times at full speed.

The motor power is transmitted to the drum through a transmission, whichresponds automatically to the tendency of the strip tension to change,to develop in the strip the desired tension.

The transmission comprises two mechanically intermeshed difierentialgearings; and an electric generator and an electric motor, associatedwith the gearings respectively; and the motor 3 and generator areinterconnected electrically, and energized respectively by adjustablefield windings, in a manner to be described.

The transmission is thus electro-mechanical, and responds as referredto, with-out the agency of any other mechanical regulating parts; andwithout any other electric regulating parts, the electrical response alltaking place in closed elec- .trical circuits.

The physical embodiment of the invention by which it may be practicedmay be considered as an electro-mechanical transmission (as referred to)adapted to be supplied with power from a motor; or may be considered asa p wer supplying unit, including the power supplying motor.

Beside the said primary object, other objects are:

To provide an apparatus comprising a transmission for transmitting thepower of a ower supplying motor to a winding drum to drive it to windstrip material thereon, the transmission constructed to respondautomatically to the tendmay of the tension in the strip to increase asvifinding goes on, in a manner to develop a desired tension in thestrip.

To provide such a transmission having means to predetermine a desiredtension that will develop in the strip as winding goes on, whether it beconstant tension; or variable tension.

To provide a transmission as referred to comprising differential gearingthrough which power the power supplying motor is transmitted to thedrum, with the motor always running at full speed; and means toautomatically vary the torque transmitted to the drum comprising anelectric generator diiferentially driven by the gearing and supplyingcurrent to drive an electric motor connected to the gearing, to developtorques at the, generator and motor, and corresponding torques at thedrum, and fields for the generator and motor, which determine by theirstrength the torques developed thereat.

An, embodiment of the invention is fully disclosed in the followingdescription taken in connection with the accompanying drawing, in which:t

Fig. 1 is a View, illustrating in diagrammatic form an electromechanical transmission, or power supplying unit, embodying theinvention in a preferred form; and, v

Fig. 2 is a fragmentary view of a part of Fig. 1 illustrating amodification; and,

'Figs. 3 and 4 are fragmentary views similar to a part of Fig, 1,illustrating other modifications.

The electro-mechanical apparatus of Fig. 1 (whether considered as apower transmission, or as a power supplying unit including the, powersupplying motor as referred to) comprises differential gearings at l and2.

In the gearing l is a spider element 3, rotatably supporting pinions 4'4meshed with differential gears 5-BJ In the gearing 2 is a spider element1, rotatably supporting pinions 8+8 meshed with differential gears 9lfl.'CoaXially connected to the differential gear is a gear I I.

The gear I l and the spider element 3 have gear teeth on theirrespective peripheries as at l2-I 3 meshed with respective gears Ml 5on. the shaft !6 ofa powersupplying motor H, whichmay be a motor of anyclass or type, but which is preferably an electric motor as shown, andfor illustrative purposes is a squirrel-cage induction motor, energizedfrom mains l8 8.

The differential gears 5 and 9 are connected 4 by respective shaftsl9-2l!, to gears 2I22, both meshed with a gear 23 on an output shaft 24connected directly to a winding drum 25 (or if preferred, connected tothe drum through speed change gears not shown).

Strip material to be wound on the drum 25 is shown at 26 as drawn fromor propelled from a processing or producing apparatus 21 An electricgenerator G, preferably ofthe direct current type, is connected by ashaft 28 to the differential gear 6.

An electric motor M, is connected to the spider element? by a shaft 29passing with clearance t rou h a coaxial bore 30 in the gear H anddifferential gear 50. p

The generator- G has a series field winding 3| and the motor M has aseries field Winding 32.

Th e motor M and generator G are electrically connected by a loopconductor 33.

As shown, a permanently closed circuitis provided comprising in series,the conductor 33, the motor M, the generator G, and their series field.windings SI and 32.

The effective ampere turns of the series field windings 2H and 32 arerespectively adjustable by rheostats 3'4 and 35 bridging them.v

The generator G and. motor M. have respective shunt field windings 36,and 31; energized with unidirectional current from supply mains 38139Q,

by WiresfiEl-Jl [-42 fromthe mai1 i 38.to one, side v of the fields, andby wires AB-J Iv from main39;

to the other side of the fields. Theeffective, am-

'pere turns of the shunt-field windings SB, and. 2"? are respectivelyadjustable bymanual rheostats; 45. and dBin the line of thewires Hand44-, in,

series with the field windings.

The field windings 3631 will preferably. bewound in the same directionfor economy in man-.

ui'acture, but when connected as shown anddescribed, current. will nowoppositely,in-them and the fields produced by the windings will beofropposite polarity.

The series field windings 3i and 32: also are connected in the saidseries .circuitfor opposite: polarity, that is to say, current flowingin the; circuit from the generator Gto the motor M (as will be referredto) flows in the series field 3-1.

in the direction to weaken the generator field (produced by the shunt.field winding 36) and flows in the series field 32in the; direction toaugment the motor field (produced by the shunt field winding 3 l) Beforedescribing the operation of the inven:-.

tion, to perform as referred to, certain characteristics may first beconsidered.

The main motor [1 puts power by gear 15% into differential gearing l atthe spider element 3 and, in the nature of differential gearings,torque. at the spider element3qdivides. between thev differential gears56, part going to the gear 2|- tending to. drive .it in the samedirection as the spider element 3;. and the gear 2| tending to drive thegear 23, outputshaft 24,- and drum 25- in the winding direction; and theother half going to thegenerator G tending to. drive. it' in thesamedirection as the spider element.

Thus, at the differential gearing I, the gear 2|- reacts on the outputgear 23 and thereby-on: thev drum load to bedriven, and causes thegenerator G to be driven; and electrical load on the generator retardsit-andcauses the gearingtorreact1 on the generator and develop loaddriving torque,

..atthegear2l.

At the. gearing. 2, the. differential gear Hland. gear ll beingconnected to the motor "H by gear element 3.

I4, are constrained thereby to run in the same direction as the spiderelement 3 of gearing and the gears 3 and run at constant speeds. Themotor M being connected to the gearing 2 therefore has its speeddetermined for it by the gearing.

However, as will be described later, the motor M, while compelled torotate at a speed determined for it by the gearing, is not driven by thegearing, but is electrically driven by current from the generator G, andtherefore tends (or tries) to run at a speed greater than thatdetermined for it by the gearing, and therefore puts motor torque in atthe spider I.

The torque of the electrically driven motor M acting through the spider1, divides between the differential gears 9 and I0, part going to thegear 22, and in the same direction as the torque applied to the gear 2|,that is, in the drum winding direction; and this part of the motortorque is applied to the drum load. The other part of the motor torquegoes to the gears Ill-l and thence through the gear M to the shaft N ofthe main motor I7, and in the same direction as the torque of the mainmotor.

Thus, in general, the motor M and generator G are driven in the samedirection; the electrical load of the generator G exerts a brake action,which causes torque to be developed at the gear 2| to drive the drum 25in the winding direction;

the generator electrical load drives the motor M;

the energy of braking at the generator G is not lost but is allrecovered and returned into the gearing by transformation at the motorM; part of the energy developed at the motor M develops torque at thegear 22 and the drum 25 in the winding direction, and is recoveredthereat; the rest of the energy of motor M develops torque at the gearsIii-l l which goes to the main motor l7 and is recovered thereat; thedrum is driven by the joint torque of the generator G and motor M at thegears 2| and 22.

As described and as is apparent, the speeds of the spider 3 of gearingand of the gears |||0 of the gearing 2 are fixed. While in same casesthe ratio of the gears |53 and |4|| may be such that the gears 3 and Irun at equal speeds, there are advantages that will appear in havingthese gear ratios such that the gear 3 runs at greater speed than thegear H, and these gears have been illustrated with such ratios.

The gears 2| and 22 (assumed for simplification to be of like diameter)are both constrained to run at the same speed by the gear 23. The speedsof the generator G and motor M, however, are different; and the speedratio thereof varies with the speed of the drum and gear 23, and thisbeing important will now be discussed.

Assuming, as a special case to make the explanation clearer, that thedrum and gear 23 are at rest, or nearly so, the gear 2| and thedifferential gear 5, Will be at rest. The difierential gear 6 andgenerator G will therefore rotate at maximum speed, twice the speed ofthe driving spider The gear 22 and differential gear 9 are also at rest,and the spider I will therefore be constrained to rotate at one half ofthe speed of the differential gear l3 and driving gear I in spite of anyeffort of the motor M to make them go faster.

The speeds of the spider element 3 and differential gear it being in aratio greater than 1-to-1 (as assumed above) the generator G willtherefore be driven faster than the motor M.

For higher drum speeds, the speed of the gen-.

6 erator G will be lower and the speed of the 'motor M will be higher,and the speed ratio will be less, as is believed to be apparent,resulting from the nature of difierential gearing.

The operation of the invention will now be described. As shown, the rollof material 26 on the drum 25 is ready for Winding to begin.

The rheostats 45 and 46 are set to energize the shunt fields 363| atsuitable values, to be referred to, and to make the explanation simpler,it will first be assumed that they alone energize the generator andmotor fields, for example by short circuiting the series fields 3| and32 by their rheostats 34 and 35. The polarities of the shunt fields arepredetermined to be correct for the generator G and motor M to run inthe same direction, with the generator G electrically driving the motorM.

The main motor having been started and having attained full runningspeed, torque applied by it to the spider element 3 divides between thegear 2| and generator G; the gear 2| reacts on the drum-gear 23 andcauses the generator to be driven; the generator G generates loadcurrent and delivers it through the motor M in the closed local seriescircuit comprising the loop 33; and the load on the generator G brakesit and causes torque to be applied at the gear 2| to the drum gear 23and to the drum 25 in the winding direction.

The electrically driven motor M drives the spider 'i, and the spiderreacts on the constantspeed rotating gear I0 and causes the gear 22 toexert torque on the drum gear 23 in the Winding direction.

It is the current through the motor M and generator G acting on theirfields that produces torques at the gears 2| and 22 and the joint torquethereof is applied to the winding drum gear 23.

As referred to, the linear speed of the strip 26 is predetermined at theapparatus 21, and a preselected tension in the strip is wanted aswinding begins. 7

The joint torque of the gears 2| and 22 can be adjusted, to give thisinitial tension, that is, adjusted for any particular installation,speed of strip 26, particular strip material, minimum diameter of drum25, etc., by adjusting the motor and genera-tor current by adjustingtheir fields at their rheostats 45-46 as will be more fully described;and when the tension has been adjusted, there will be a speed of thedrum corresponding to it; and this speed will be the maximum speed; andthe gears 2| and 22 being geared to the drum gear 23 will have acorresponding maximum speed.

At this high speed of the gears 2 |-22, the generator G will havev arelatively low speed, and the motor M a relatively high speed, due tothe gearing interconnections, as explained hereinbefore.

The potential of the generator G at this low speed will be relativelylow; and the relatively high speed of the motor M will give the motorrelatively high counterpotential, in opposition to that of thegenerator; and the current produced by the generator and driving themotor, and producing the said joint torque will therefore be relativelylow.

As the winding then proceeds, and the roll diameter on the drumincreases, the tension in the strip 26 acts on an increasing radius; thesaid joint torque exerted on it, is not able to continue to drive it atthe same speed, and it slows down;

and this slows down the gear 23 and the equalspeed gears 2| and 22. y i

demand 7 'The generator G thereupon responds to go faster; and the motorM is constrained by the gearing to go slower; this being inherent in thegearing as described above.

The potential of the generator G, accordingly rises, and the opposingcounterpotential of the motor falls; and more generator currentaccordingly flows. Phis loads and brakes the generator G more, and itproduces more torque at the gear 2|, and the increased current in themotor produces more torque at the gear 22, and the joint torque rises.

Thus as the roll diameter increases, the current increases and moretorque is applied to the drum and tends to maintain the strip tension atdecreasing drum speed.

The strength of the fields of the generator G and motor M can beadjusted to maintain the strip tension at a substantially constant,preselected value, if desired, and this mode of operation will now firstbe explained.

For some intermediate strengths of the motor and generator fields,determined by a setting of the rheostats 55-48 (assuming the serieswindings 3| and 32 to be out out as refered to), the relatively lowspeed of the generator G and relatively high speed of the motor M willcause a certain current to flow and develop certain torques at the gears2| and 22. The rheostats can be adjusted until a current value isproduced that produces a joint torque that gives the desired striptension.

As described, the current increases as winding goes on, and thisincreases the joint torque, It has been found that the increase ofcurrent and joint torque is in general proportional to the increase ofroll diameter, so that the tension tends to remain-constant. Anydeviation from this proportionality will be in the direction of too fastan increase of current and torque due to the increasing speed ratio ofthe generator and motor speeds as described, and in the direction ofincreasing tension. This may be corrected by introducing resistance atthe rheostat 34 to divert some of the current into the generator reverseseries field winding 3|, which will be in the direction to weaken thegenerator field.

The generator and motor shunt fields due to the windings 3e and 31remaining unchanged, whatever current flows reacts on these fields toproduce torque as before, the only difference being that the current andtorque now will not increase as rapidly as before, and, by the seriesfield adjustment, can be caused to increase at a rate to keepthe striptension substantially constant.

If as referred to it be desired to have the tension in the stripdecrease as winding goes on instead of remaining substantially constantas described; the amount of current diverted into the generator seriesfield winding 3| by the rheostat 34 may be adjustable increased, so thatthe rate of increase of current and torque with increase of roll radiuswill be reduced. And similarly if it be desired to have the tensionincrease, the amount of current diverted to the winding 3| maybe'decrea'sed.

By these adjustment means, which can be set and fixed, thedes'i-redtension in the strip roan be set at the beginning of the windingoperation, and will be maintained at substantially constant tension aswinding proceeds and the roll increases in diameter; or can be made tobe an increasing tension; or made to be a decreasing tension; and whenthe tension is to be increasing-or 8 decreasing, its rate of change forincreasing roll diameter can likewise be adjusted.

Having described the universal adjustment in some detail, a moregeneralized formulation thereof may now be iven.

The fields of the generator G and motor M are adjusted at the windings3G and 31 to fixed constant values, and may be considered as basefields. The generator G due to its base field generates current whichdrives the motor M. The current reacts on the base fields of both thegenerator and motor to develop torque and their joint torque is appliedon the winding drum 24; and the joint torque produces tension in thestrip 26.

The joint torque may be adjusted to the particular material andinstallation, by adjusting the strength of the base fields to adjust thestrip tension at the beginning of winding.

The generated current increases as winding goes on, due to speeding upof the generator and slowing down of the motor and the joint torqueaccordingly increases; but increasing torque is in general needed on thedrum due to the increasing radius of the roll. The increasing currentreacting on the base fields automatically provides increasing torque.

Due to fixed base field strength, the rate of torque increase iscommensurable with the rate of current increase.

If constant tension on the strip is wanted, and if for any reason thecurrent does not increase at the rate to give constant tension, the rateof increase of the current can be adjusted to bring this about byadjusting the effectiveness of the series field winding 3 In general thecurrent will tend to increase too rapidly for constant tension and theseries field winding 3| will accordingly need to be a reverse winding,and the current in the winding will weaken the field and reduce the rateof current increase, without affectin the base field strength.

A similar slowing down of the rate of current increase can be producedby adjusting the motor series field winding 32, which strengthens itsfield and increases its countervoltage.

Obviously, if for any reason the current should tend to increase tooslowly for constant tension, its rate of increase can be accelerated togive constant tension by making the series winding 3| an assistingwinding instead of a reverse winding. An arrangement to do this is shownin the modification of Fig. 2, where the winding 3| is provided with areversing switch 41 to reverse the direction of current in the winding,subject in value to the rheostat 34.

If a decreasing tension is wanted in the strip, calling for a stillgreater decrease in the rate at which the current increases, theopposition by the series field winding 3| can be adjusted to be moreefiective.

If an increasing tension in the strip is wanted, calling for an increasein the rate of current increase, the opposition of the series winding 3|can be made completely ineffective, or the winding can even be made toassist by utilizing the throw reversing switch 41 in the modification ofFig. 2.

It being a part of the invention to make the transmission universallyadjustable, adjustable rheostats 45--46 for the shunt field windings andrheostats 34-35 for the series field windings have been illustrated andthe universal adjustment of the transmission thereby has been described.However, as contemplated by the objects of the invention, theseadjustments are not in every case necessary and may be omitted. Giventhe data of an installation as to drum diameter, strip speed, etc. andthe requirements of performance as to desired tension in the strip; andknowing the characteristics of the transmission as to the potential ofthe unidirectional current mains 38-39 and the number of turns in theseveral field windings, etc., then fixed resistances may be provided inplace of the rheostats; or the number of turns in the field windings maybe preselected, and utilized without either fixed resistances rrheostats.

The apparatus may therefore be originally built to give the desiredstrip tension (constant, increasing or decreasing), without making itadjustable.

As described, the gear 3 of gearing I, and the gear I 0 (or gears IO-II) of gearing 2, run at constant speeds, and at a fixed speed ratio, andthis is preferably done by interconnecting them together. Absolutelyconstant speeds for these gears are not essential and are not evenactually present in the arrangement of Fig. 1 because of the slightlyvariable slip of the induction motor I'I under variable load. Also, anabsolutely fixed speed ratio therebetween is not essential; but ispreferable because of simplification of the gearings which it makespossible.

In Fig. 1, the preferably fixed speed ratio and substantially constantspeeds are both provided by rotatively connecting the gear 3 and gear ID(or gears I0-I I) to the power motor I! by gears I and I4 on the motorshaft I6.

An advantage results from the described arrangement in that it makespossible a free circulation of power within the transmission thatcontributes to the recovery of power from the generator G without lossas referred to.

That is, power from the motor I1 goes to the spider gear 3; a part ofits goes to the generator G and thence to the motor M, and to the spiderI; and a part of the power to the spider I goes to the gear ID (or gearsIIi-I I), and thence to gear I4. At this point, the power from thespider 'I may be considered as going from the gear I4 back to the powermotor IT, or may be considered as going from the gear I4 to gear I5 andthence to gear 3, which is the same thing, be-

cause in either case, the power assists the motor and substantiallyconstant speeds and circulation of power can be had with otherarrangements than that of Fig. 1.

For example as shown in simplified form in Fig. 3, the spider 3 may bedriven by the motor I I, through a gear 48, as shown in solid line, andthe spider 3 may be rotatively connected to the gear II through an idlergear 48, the gears 3 and II being of appropriate relative diameters.

Or as indicated in Fig. 3 in dotted line the motor I! may be connectedto the gear II by a gear 50.

In this connection and as indicating the scope of the invention, thedesirable substantially constant speeds and speed ratio of the gears 3and II) (or I0-I I) may be provided without the above described or anyinterconnection between them; and one possible modification for doingthis is shown in Fig. 4.

Here, the gear 3 of gearing I is driven as before by the induction motorI] through a gear 10 I5, and therefore runs at a substantially constantspeed as before.

The gear II is geared by a gear 5| to another induction motor 52, andthe output torque at the gear II drives the motor 52 above synchronousspeed as a generator, and it supplies electrical load current back toits energizing supply lines 53 without loss of the energy driving it. Asis known, when an induction motor is thus energized and driven abovesynchronous speed as a generator, it develops load torque that increasesvery rapidly. The speed of the gear II therefore will be prevented fromthe increasing except very little and will therefore be constrained torun at substantially constant speed. In consequence, both gears 3 and IIhave substantially constant speeds and a substantially constant speedratio.

It follows that changes and modifications may be made in thetransmission as described for Fig. 1 without departing from the spiritof the invention or sacrificing its advantages and the invention iscomprehensive of all such changes and modifications that come within thescope of the appended claims.

I claim:

1. A power transmission for driving a rotary load, comprising: anelectric generator; an electric motor; a first and a second difierentialgearing, each comprising a spider element rotatably supporting a pinionand two differential gear elements meshed with the pinion; the spiderelement of the first gearing and a difierential gear of the secondgearing being interconnected to rotate at a predetermined speed ratioand adapted to be connected to a power supplying motor; a differentialgear of the first gearing connected to the generator to drive it; theelectric motor electrically connected to the generator to beelectrically driven by it; the spider element of the second gearingconnected to the electric motor to be driven by it; means adapting theother difierential gears of the gearings to be connected to the load todrive it at predetermined respective speed ratios with the load at allspeeds of the load. i

2. A power transmission for driving a rotary load, comprising: anelectric generator; an electric motor; a first and a second differentialgearing each having three rotary elements; a rotary element of eachgearing interconnected to rotate at a predetermined speed ratio andadapted to be connected to a power supplying motor; another rotaryelement of the first gearing connected to the generator to drive it; theelectric motor electrically connected to the generator to beelectrically driven by it; another rotary element of the second gearingconnected to the motor to be driven by it; connection means at the thirdrotary elements of the gearings adapting them to be connected to theload to drive it, and to each be constrained to rotate at apredetermined speed ratio with the load at all speeds of the load; therespective rotary elements that are interconnected being selected tocause the speed of the generator to increase and the speed of theelectric motor to decrease as the speed of the load decreases.

3. In an apparatus for winding on a drum or the like, strip materialthat is supplied to the drum at a substantially constant linear speed,and for concurrently controlling the tension in the strip; an electricgenerator; an electric motor electrically connected to the generator tobe electrically driven by generator current; a first and a secondgearing comprising each a rotary power output element; the first gearinghaving a rotary power receiving element adapted to receive power from aconstantly running power motor, and the first gearing adapted totransmit power diiierentially to the generator, and to the drum throughthe rotary output element of the first gearing at a predetermined speedratio and in the direction to wind the strip on the drum; the secondgearing having a rotary element interconnected at a predetermined speedratio with the power receiving element of the first gearing; the secondgearingadapted to receive power from the electric motor and transmit itdifferentially to the said interconnected rotary element, and to thedrum through the output element of the second gearing at a predeterminedspeed ratio and in the direction to wind the strip on the drum; the saidinter= connected rotary element and power receiving ele ment beingpreselected in the gearings to cause the generator speed to increase andthe motor speed to decrease as the speed of the drum decreases uponincrease of diameter of the roll of material being wound thereon, and toeffect a corresponding increase of generator current to the electricmotor; respective exciting field wind ings for the generator and motor,and circuit means for energizing them with current; means to adjustablyvary the energizing current of the field windings to vary the currentproduced by the generator and correspondingly vary the torque of theelectric motor and of the generator to correspond ingly vary the torquesdifierentially transmitted to the drum to correspondingly adjust thetension in the strip.

4. An apparatus as described in claim 3 and in which the generator fieldhas an auxiliary field winding energized proportionally to the gencratorcurrent; and means is provided to adjustably vary the effective ampereturns of the auxiliary field winding to correspondingly adjust the rateof increase of the generator current as its speed increases.

5. In an apparatus for winding on a drum or the like, strip materialthat is supplied to the drum at a substantially constant linear speed,for concurrently controlling the tension in the strip; an electricgenerator; an electric motor electrically connected to the generator tobe electrically driven by generator current; a first and a secondgearing comprising each a rotary power output element; the first gearinghaving a rotary power receiving element adapted to receive power from aconstantly running power motor, and the first gearing adapted totransmit power differentially to the generator, and to the drum throughthe rotary output element of the first gearing at, a predetermined speedratio and in the direction to wind the strip on the drum; the secondgearing having a rotary element interconnected at a prev determinedspeed ratio with the power receiving element of the first gearing; thesecond gearing adapted to receive power from the electric motor andtransmit it difierentially to the said interconnected rotary element,and to the; drum through the output element of the second gearing at apredetermined speed ratio and in the direction to Wind the strip on thedrum; the said interconnected rotary element and power receiving elementbeing preselected in the gearings to cause the generator speed toincrease and the motor speed to decrease as the speed of the drumdecreases upon increase of diameter of the roll of material being woundthereon, and to efiect a corresponding change of generator current tothe electric motor; respective exciting field; windings for thegenerator and motor, and circuit means for energizing them with current;means to ad justably vary the energizing current of the field windingsto vary the current produced by the generator and correspondingly varythe torque of the electric motor and of the generator to correspondinglyvary the torques differentially transmitted to the drum tocorrespondingly adjust the tension in the strip; the generator having anauxiliary field winding energized proportionally to the generatorcurrent; and means to adjustably vary the effective ampere turns of theauxiliary field winding to correspondingly adjust the rate of change ofthe generator current as its speed increases, to correspondingly modifythe said adjusted tension in the strip to cause it to be op tionallysubstantially a constant tension or a dc creasing tension or anincreasing tension as the diameter of the wound material on the drumincreases.

6. In an apparatus for driving a winding drum to wind thereon stripmaterial supplied thereto at a substantially constant rate and toconcurrently control the tension in the strip; an electric generator andan electric motor and an intercom necting circuit between them forelectrically driving the motor by current from the generator: respectivefield windings for the generator and motor and circuit means foradjustably encrgiaing them; a difierential gearing transmission to whichthe generator and motor are mechanically connected; the transmissioncomprising two rotary output elements, and being arranged to re ceivepower from a continuously running power motor and from the electricmotor, and to differentially drive the generator and to apply said powerto develop respective torques at the rotary output elements determinedin value by the adjusted energization of the fields and thecorresponding value of generator current; connection means at the rotaryoutput elements for drivingly connecting them to the drum to apply bothsaid torques thereto to drive the drum in the winding direction, tocause the drum to wind the strip thereon in a roll of increasing radiusand to develop tension in the strip, determined in value by thegenerated current effected by the adjust ment of the fields; and theconnection means between the rotary output elements and the drum beingsuch as to cause the rotary elements to each have a constant speed ratiowith the drum and whereby upon a decrease of drum speed caused byincreasing roll radius, the transmission reacts to cause the generatorto increase in speed and the motor to decrease in speed, to cause thegenerator to develop more current in itself and in the motor to causethe said torques to increase and maintain tension in the strip.

7. In an apparatus for driving a winding drum to wind thereon stripmaterial supplied thereto at a substantially constant rate and toconcurrently control the tension in the strip; an electric generator andan electric motor and an interconnecting circuit between them forelectrically driving the motor by current from the generator; respectivefield windings for the generator and motor and circuit means foradjustably energizing them; a differential gearing transmission to whichthe generator and motor are mechanically connected; the transmissioncomprising two rotary output elements, and being arranged to. receivepower from a continuously running power motor and from the electricmotor, and to differentially drive the generator and to apply said powerto develop respective torques at the rotary output elements determinedin value by the adjusted energization of the fields and thecorresponding value of generator current; connection means at the rotaryoutput elements for drivingly connecting them to the drum to apply bothsaid torques thereto to drive the drum in the winding direction, tocause the drum to wind the strip thereon in a roll of increasing radiusand to develop tension in the strip, determined in value by thegenerated current effected by the adjustment of the fields; and theconnection means between the rotary output elements and the drum beingsuch as to cause the rotary elements to each have a constant speed ratiowith the drum and whereby upon a decrease of drum speed caused byincreasing roll radius, the transmission reacts to cause the generatorto increase in speed and the motor to decrease in speed, to cause thegenerator to tend to develop more current in itself and in the motor tocause the said torques to tend to increase and maintain tension in thestrip; a series field Winding for the generator in which the generatedcurrent fiows; and means to adjust the effectiveness of the ampere turnsof the series field winding to modify the tendency of the current toincrease, to optionally adjustably cause the tension in the strip to besubstantially constant or to increase or to decrease.

8. In an apparatus for driving a strip material winding drum or likeload; an electric generator, and an electric motor, and aninterconnecting circuit by which current from the generator drives themotor; a first differential gearing comprising two rotary power outputelements and a rotary .power input element and transmission meansarranged to transmit power to the input element from a continuouslyrunning power supplying motor, to drive it at a speed commensurable withthat of the power supplying motor, and one output element connected tothe electric generator to drive it; a second difierential gearingcomprising two rotary power output elements, and a rotary power inputelement, the power input element connected to the electric motor to bedriven thereby, and an output element having a driving connection withthe input element of the first gearing which constrains them to run at apredetermined speed ratio; respective field windings for the generatorand motor and circuit means for energizing them at selected values; andthe other output elements of the two gearings being respectivelyconnected to a winding drum to drive it in the winding direction byconnections that constrain them to rotate always at speeds commensurablewith that of the drum; and the output elements of the differentialgearings to which said drum connections are made being preselected tocause the speed of the generator to increase and the speed of the motorto decrease upon a decrease of speed of the drum.

9. In an apparatus for driving a strip material winding drum or likeload; an electric generator and an electric motor and interconnectingcircuit means between them by which the motor is driven by generatorcurrent; a first differential gearing comprising a power input spiderelement rotatably supporting a pinion, and two output differential gearsmeshed with the pinion, and transmission means arranged to transmitpower to the spider element from a continuously running power supplyingmotor to drive it at a speed commensurable with that of the motor andone output differential gear connected to the generator to drive it; asecond difierential gearing comprising a spider element rotatablysupporting a pinion and two output differential gears meshed with thepinion, and the spider element being connected to the electric motor tobe driven thereby, and one output differential gear and the spiderelement of the first gearing having a connection therebetween thatconstrains them to rotate at a predetermined speed ratio; respectivefield windings for the electric motor and generator and circuit meansfor energizing them at selected values; the other two outputdifferential gears of the two gearings adapted to be connectedrespectively to a winding drum by connections through which they bothdrive the drum in the winding direction and which maintainspredetermined speed ratios between them respectively and the drum at allspeeds of the drum.

10. In an apparatus for driving a winding drum to wind 'a roll of stripmaterial thereon supplied thereto at a constant linear speed; anelectric generator and an electric motor, interconnected electrically tocause the motor to be driven by generator current; a power supplyingmotor; a difierential gearing transmission, comprising a rotary elementadapted to receive power from the power supplying motor; and comprisinga pair of rotary elements adapted to be connected to a winding drum; andcomprising rotary elements connected respectively to the generator todrive it and to the electric motor to be driven by it; anddifferentially transmitting generator load torque and electric motordriving torque to the pair of rotary drum driving elements to drive thedrum in the winding direction; the rotary elements selectively arrangedto drive the generator at increasing speed and to constrain the motor torun at decreasing speed upon decreasing speed of the drum caused byincreasing radius of the material roll being wound on the drum.

11. An apparatus for driving a strip material winding drum or like loadcomprising: an electric generator; an electric motor; a first and asecond differential gearing; the first gearing adapted to receive powerat a power receiving element at substantially constant speed thereoffrom a continuously running power supplying motor and to differentiallytransmit the power to a first and a second rotary element of the gearingand from the second rotary element to the generator to drive it;electric circuit means to which the generator supplies load current tothe electric motor to electrically drive it; the second gearing adaptedto receive power at a power receiving element from the electric motorand differentially transmit the power to a first and a second rotaryelement of the second gearing; means constraining the second rotaryelement of the second gearing to run at substantially constant speed;power transmitting connections at the respective first rotary elementsof the gearings adapted to drivingly connect the rotary elements to awinding drum to both drive it in the winding direction, and to constrainthe rotary elements to have predetermined respective speed ratios withthe drum at all speeds of the drum; the rotary elements to which theelectric motor and generator are connected being selected to cause thegenerator to increase in speed and the motor to decrease in speed upon adecrease in speed of the drum caused by increasing radius of the stripmaterial being wound on the drum.

12. In an apparatus for driving a strip material winding drum or likeload; an electric generator; an electric motor; a first and a seconddifferential gearing each having three rotary elenients; means forconstraining a rotary element of each gearing to rotate at substantiallyconstant speeds, said means for one of the rotary elements being asubstantially constant speed power supplying motor, to which it isadapted to be connected; another rotary element of the first gearingconnected to the generator to drive it; the electric motor electricallyconnected to the generator to be electrically driven by it; anotherrotary velement of the second gearing connected to the motor to bedriven by it; connection means at the third rotary elements of thegearings adapting them to be connected to a winding drum to drive it inthe winding direction, and to each be constrained to rotate at apredetermined speed ratio with the drum at all speeds of the drum; therotary elements to which the electric motor and generator are connectedbeing selected to cause the generator to increase in speed and the motorto decrease in speed upon a decrease in speed of the drum caused byincreasing radius of the strip material being wound on the drum.

13. In an apparatus for driving a strip material winding drum or likeload; an electric generator; an electric motor; a first and a seconddifferential gearing, each comprising a spider element rotatablysupporting a pinion and two differential gear elements meshed with thepinion; means for constraining the spider element of the first gearingand a differential gear of the second gearing to rotate at substantiallyconstant speeds, said means for the spider element being a substantiallyconstant speed power supplying motor to which it is adapted to beconnected; a differential gear of the first gearing connected to thegenerator to drive it; the electric motor electrically connected to thegenerator to be electrically driven by it; the spider element of thesecond gearing connected to the electric motor to be driven by it; meansadapting the other differentialv gears of the gearings to be connectedto the drum to drive it in the winding direction at predeterminedrespective speed ratios with the drum at all speeds of the drum.

let. In an apparatus for driving a strip material winding drum or likeload; an electric generator; an electric motor; a first and a seconddifierential gearing each having three rotary elements; meansconstraining a rotary element of each gearing to run at substantiallyconstant speed, the said means for the rotary element of the firstgearing being a substantially constant speed power supplying motor towhich it is adapted to be connected; another rotary element of the firstgearing connected to the generator to drive it; the electric motorelectrically connected to the generator to be electrically driven by it;another rotary element of the second gearing, connected to the motor tobe driven by it; connection means at the third rotary elements of thegearings adapting them to be connected to a winding drum to drive it inthe winding direction, and to each be constrained to rotate at apredetermined speed ratio with the drum at all speeds of the drum; therespective rotary elements that are constrained to run at constant speedbeing selected to cause the speed of the generator to increase and thespeed of the electric motor to decrease as the speed of the drumdecreases.

15. In an apparatus for winding on a drum or the like, strip materialthat is supplied to the drum at a substantially constant linear speed,

and for concurrently controlling the tension in the strip; an electricgenerator; an electric motor electrically connected to the generator tobe electrically driven by generator current; a first and a secondgearing comprising each a rotary power output element; the first gearinghaving a rotary power receiving element adapted to receive power atsubstantially constant speed from a constantly running power motor, andthe first gearing adapted to transmit power diiferentially to thegenerator, and to the drum through the rotary output element of thefirst gearing at a predetermined speed ratio and in the direction towind the strip on the drum; means constraining a rotary element of thesecond gearing to run at substantially constant speed; the secondgearing adapted to receive power from the electric motor and transmit itdifferentially to the said constant speed rotary element of the secondgearing, and to the drum through the output element of the secondgearing at a predetermined speed ratio and in the direction to wind thestrip on the drum; the said constantspeed rotary elements beingpreselected in the gearings to cause the generator speed to increase andthe motor speed to decrease as the speed of the drum decreases uponincrease of diameter of the roll of material being wound thereon, and toefiect a corresponding increase of generator current to the electricmotor; respective exciting field windings for the generator and motor,and circuit means for energizing them with current; means to adjustablyvary the energizing current of the field windings to vary the currentproduced by the generator and correspondingly vary the torque of theelectric motor and of the generator to correspondingly vary the torquesdifferentially transmitted to the drum to correspondingly adjust thetension in the strip.

16. In an apparatus for winding on a drum or the like, strip materialthat is supplied to the drum at a substantially constant linear speed,and for concurrently controlling the tension in the strip; an electricgenerator; an electric motor electrically connected to the generator tobe electrically driven by generator current; a first and a secondgearing comprising each a rotary power output element; the first gearinghaving a rotary power receiving element adapted to receive power atsubstantially constant speed from a constantly running power motor, andthe first gearing adapted to transmit power differentially to thegenerator, and to the drum through the rotary output element of thefirst gearing at a predetermined speed ratio and in the direction towind the strip on the drum; means constraining a rotary element of thesecond gearing to run at substantially constant speed; the secondgearing adapted to reecive power from the electric motor and transmit itdifferentially to the said constant speed rotary element of the secondgearing, and to the drum through the output element of the secondgearing at a predetermined speed ratio and in the direction to wind thestrip on the drum; the said constant speed rotary elements beingpreselected in the gearings to cause the generator speed to increase andthe motor speed to decrease as the speed of the drum decreases uponincrease of diameter of the roll of material being wound thereon, and toeirect a corresponding change of generator current to the electricmotor; respective exciting field windings for the generator and motor,and circuit means for energizing them with current; means to adjustablyvary the energizing current of the field windings 17 to vary the currentproduced by the generator and correspondingly vary the torque of theelectric motor and of the generator to correspondingly vary the torquesdifferentially transmitted to the dr'umto correspondingly adjust thetension in the strip; the generator having an auxiliary field windingenergized proportionally to the generator current; and means toadjustably vary the effective ampere turns of the auxiliary fieldwinding to correspondingly adjust the rate of change of the generatorcurrent as its speed increases, to correspondingly modify the saidadjusted tension in the strip to cause it to be optionally substantiallya constant tension or a decreasing tension or an increasing tension asthe diameter of the wound material on the drum increases.

17. In an apparatus for driving a strip material winding drum or likeload; an electric generator, and an electric motor, and aninterconnecting circuit by which current from the generator drives themotor; a first differential gearing comprising two rotary power outputelements and a rotary power input element and transmission meansarranged to transmit power to the input element at substantiallyconstant speed from a continuously running power supplying motor, andone output element connected to the electric generator to drive it; asecond differential gearing comprising two rotary power output elements,and a rotary power input element, the power input element connected tothe electric motor to be driven thereby, means constraining an outputelement to run at substantially constant speed; respective fieldwindings for the generator and motor and circuit means for energizingthem at selected values; and the other output elements of the twogearings being respectively connected to a winding drum to drive it inthe winding direction by connections that constain them to rotate alwaysat speeds commensurable with that of the drum; and the output elementsof the differential gearings to which said drum connections are madebeing preselected to cause the speed of the generator to increase andthe speed of the motor to decrease upon a decrease of speed of the drum.

18. In an apparatus for driving a strip material winding drum or likeload; an electric generator and an electric motor and interconnectingcircuit means between them by which the motor is driven by generatorcurrent; a first differential gearing comprising a power input spiderelement rotatably supporting a pinion, and two output differential gearsmeshed with the pinion, and transmission means arranged to transmitpower to the spider element from a continuously running power supplymotor to drive it at substantially constant speed and one outputdifferential gear connected to the generator to drive it; a seconddifferential gearing comprising a spider element rotatably supporting apinion and two output differential gears meshed with the pinion, and thespider element being connected to the electric motor to be driventhereby, and means constraining one output differential gear to run atsubstantially constant speed; respective field windings for the electricmotor and generator and circuit means for energizing them at selectedvalues; the other two output differential gears of the two gearingsadapted to be connected respectively to a winding drum by connectionsthrough which they both drive the drum in the winding direction andwhich maintains predetermined speed ratios between them respecthe firstgearing and one differential gear of the second gearing interconnectedto rotate at a predetermined speed ratio and adapted to be connected toa continuously running power supplying motor; one differential gear ofthe first gearing connected to the generator to drive it; the electricmotor being electrically connected to the generator to be electricallydriven by its current output; the spider element of the second gearingbeing connected to the motor to be driven by it; connection means at theother difierential gears of both gearings adapting them to be connectedto the load to drive it jointly; and to each be constrained to rotate ata predetermined speed ratio with the load, at all speeds of the load,the said interconnection causing the speed of the generator to increaseand the speed of the motor to decrease as the speed of the loaddecreases.

20. A power transmission adapted to receive power from a power motor andapply torque to a rotary load to drive it; the transmission constructedto be responsive to slowing down of the load to automatically increasethe load-applied torque and vice versa; the construction of thetransmission comprising two differential gearings, one differentialgearing comprising a rotary spider element adapted to receive power fromthe power motor, and rotatably supporting a pinion meshed with twodifferential gears, and one differential gear connected to an electricgenerator to drive it and the other difierential gear connected to theload to apply driving torque thereto; the generator having a loadcircuit; the other differential gearing comprising a rotary spiderelement rotatably supporting a pinion meshed with two difierential gearsand one differential gear adapted to receive power from the power motor,and the other differential gear connected to the load to apply drivingtorque thereto, and the spider element connected to an electric motor,driven electrically by current in the generator load circuit; the spiderelement and dilferential gear that as aforesaid receive power from thepower motor being interconnected to constrain them to rotate at apredetermined speed ratio.

21. In a winding apparatus for winding strip material in a coil on awinding drum supplied to the drum at constant linear speed; a powertransmission adapted to receive power from a power motor and applytorque to the drum to drive it; the transmission constructed to respondto the slowing down of the drum due to increasing diameter of the coilas winding goes on, to increase the torque applied to the drum tomaintain tension in the strip at a desired value; said construction ofthe transmission comprising: two differential gearings, one differentialgearing comprising a rotary spider element adapted to receive power fromthe power motor, and rotatably supporting a pinion meshed with twodifferential gears, and one difierential gear connected to an electricgenerator to drive it and the other diiferential gear connected to thedrum to apply driving torque thereto; the generator having a loadcircuit; the other difierential gearing comprising a rotary spiderelement rotatably supporting a pinion meshed with two differential :19gears and one differential gear adapted to receive power from the powermotor, and the other differential gear connected vto the drum to applydriving torque thereto, and the spider element connected to an electricmotor, driven electrically by current in the generator load circuit;

LEV A. TROFIMOV.

References Cited in the file :of :this patent UNITED STATES PATENTSNumber

